Arduino MCP23017 16 bit IO Expander. 8 chips,128 added pins!

Here are 8 mcp23017 chips daisy-chained using an Arduino pro mini. There are now 128 added addressable pins using the I2c SDA and SCL pins. I’m not really sure what uses this project could have, but it was fun to make! One possible evolution of it could be as a midi controller…maybe a lighted fretboard on a guitar that shows you the notes to play…or something.

In the code there are two functions that will generate patterns for the LEDs: “Propeller” and “Clockwise”. You can watch the video to see the output of each routine.

The delay time between LED firings is dependent on the ultrasonic distance sensor: (LV-MaxSonar-EZ0 by MaxBotix). That is, the closer the object to the front of the sensor, the smaller the delay interval between pin firings.

This is cool! I am trying to get into the technology field, my interest is in front end web development. I am taking a guess that the code is Java, but I could be wrong. Anyway all this is really cool! Have a nice day! 🙂